Aminomercuration alkenes

There are several methods available for the electrophilic addition of hydrogen and nitrogen to alkenes, dienes and alkynes. While the direct electrophilic addition of amines to these substrates is not feasible, aminomercuration-demercuration affords a very useful indirect approach to such amines. The addition of amides to C—C multiple bonds can be effected directly through the Ritter reaction or by the less direct, but equally useful, amidomercuration-demercuration process using either nitriles or amides. Similarly, H—N3 addition to alkenes can be carried out directly or via mercuration to produce organic azides. 

A wide variety of alkenes have been shown to undergo aminomercuration-demercuration, including alkenes bearing alcohol, ester, acid, amide, imide, urea, urethane, ether, sulfide and aryl groups.194... 

Organomercurials prepared by oxy- or aminomercuration of alkenes are converted to Li reagents ... 

In this connection, intramolecular Michael addition of 0-carbamates to a,3-unsaturated esters (Scheme 60)," iodo cyclization of allylic and homoallylic trichloroacetamidates" or aminomercuration of alkenic carbamates" has been used for the preparation of amino alcohols. 

The aminomercuration-demercuration reaction has provided two examples for primary to secondary amine conversion.In one, Markovnikov addition of the aminomercurial (10) to an alkene, followed by ligand exchange with sodium hydroxide and subsequent reduction with sodium borohydride, yields the secondary amine (11) in a one-pot reaction (Scheme 10). In the other,vicinal diamines (12) are the products from the one-pot reaction of alkenes with tetrafluoroboric acid and mercury(ll) oxide in the presence of excess primary amine (Scheme 11). Both reactions work equally well with secondary amines. 

Cyclic secondary amines are also produced by the ring expansion of O-sulphonyloximes via a Beckmann rearrangement/ the cyclization of a,aliphatic diamines by a ruthenium catalyst/ the palladium-promoted ring closure of amino-alkenes/ and the sulphonamidomercuration of 1,4- and 1,5-dienes. The latter two reactions form part of a wealth of new literature on the amination of olefins and acetylenes via aminomercuration " and via palladium catalysis. ... 

Three very detailed papers concerning solvomercuration and demercuration have appeared, and Barluenga and co-workers have published several papers dealing with aminomercuration and demercuration of alkenes, the chemistry of which is summarized in Scheme 10. These authors have also shown that propargyl alcohol may be aminomercurated to give either 1,2-di-imines or 2-aminopropionamidines. ... 

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